Irregularities in the terrain over which a snowmobile travels produce displacements and deflections of its rear suspension assembly. A conventional rear suspension supports an endless track, which is tensioned to surround a pair of parallel slide rails, a plurality of idler wheels and at least one drive wheel or sprocket. A shock absorbing mechanism involving springs, hydraulic dampers, and/or other shock absorbing elements, urges the slide frame assembly and the chassis (also known as a frame) of the snowmobile, which includes a tunnel, apart against the weight supported above the suspension in a static condition.
When an irregularity such as a bump occurs on the terrain, the rear suspension allows the slide rails to move toward the tunnel. Similarly, when a depression occurs on the terrain, the rear suspension allows the slide rails to move away from the tunnel. In some cases, the terrain provides configurations for which the snowmobiles cannot or can only minimally accommodate. This is the case, for example, when the snowmobile is side-hilling or moving in reverse.
A snowmobile is said to be side-hilling when it is positioned at least partially sideways on a slope. In such a position, an uphill part of the rear suspension is disposed vertically above a downhill part of the rear suspension. This can increase the resistance to lean the snowmobile into the slope to keep the snowmobile horizontal.
When a snowmobile is driven in reverse, particularly on soft snow, the rear portion of the track can dig into the snow and cause the snowmobile to become stuck.
Therefore, there is a need for a rear suspension assembly for a snowmobile that allows the snowmobile to drive on different terrain configurations.
There is also a need for a snowmobile having such a suspension.
There is also a need for a kit for converting an existing rear suspension to such a suspension.
There is also a need for a method for making such a conversion.